The Eye care cosmeceutical products are one of the top selling cosmetics in the world. The skin around the eye is very thin and when blood passes through the large veins close to the surface of the skin it can produce a bluish tint. The more transparent the skin, which is also an inherited trait, the darker the circles appear.
Hyperpigmentation (a high amount of melanin in the skin) is often the culprit for dark circles under the eyes, as is engorged blood vessels in the thin skin under the eye. This is especially common for the fair-skinned people. Also fatigue, excessive sun exposure, dehydration, and medical conditions related to renal, thyroid and even genetics could cause dark circles to appear.
The fine lines at the corner of one's eyes are commonly referred to as “crow's feet”. This area has fewer oil glands than rest of the face, and is susceptible to extra dryness and formation of wrinkles.
Puffiness of eyes and eye bags are two different kinds of conditions. While fluid retention is the main cause of puffy eyes, a common occurrence in the morning, as fluid builds up while sleeping and baggy eyes are the result of accumulated fat in the eye area. Over time, the septum surrounding the eyeball socket weakens, which causes the outer layer of fat within the socket to sink forward—resulting in pouches, or bags.
Tyrosinase, a single-chain glycoprotein enzyme essential to pigment formation in mammals, is specifically localized in melanocytes, which occur primarily in the skin, hair bulbs, and eyes. Tyrosinase, the rate-limiting enzyme in melanin synthesis, is expressed specifically in pigment-producing cells. Tyrosinase converts tyrosine to dihydroxyphenylalanine (DOPA) and then to dopaquinone. Subsequently, dopaquinone is converted to dopachrome, through auto-oxidation, and finally to dihydroxyindole or dihydroxyindole-2-carboxylic acid (DHICA) to form melanin (brown-black pigment). Tyrosinase enzyme inhibitors have a greater role to play for treating hyper pigmentation of the skin around eyes.
Hyaluronic Acid (HA), a natural glycosaminoglycan biopolymer, is present in the tissues. It has an enormous water binding capacity (up to 1,000 times its weight) and it forms high viscosity hydrated polymers. More than 50% of the total amount of body HA is present in skin (in dermis and epidermis). Hyaluronic acid is a basic building block of the dermis. It stabilizes the intercellular structures of connective tissues and forms the elastoviscous fluid matrix in which collagen and elastin fibers are embedded. It also promotes the renewal of keratinocytes and its ability to retain water helps in proper hydration of the skin. The amount of HA in the skin decreases with aging and photo aging process. Hyaluronidase is an enzyme that degrades HA resulting in reduced dermal hydration, disorganization of collagen and elastin fibers and increased skin wrinkling and folding. Hyaluronidase Inhibitors are known to have potential benefits in preventing and treating crow's feet type of fine line wrinkles.
The free radical damage of the skin around the eyes causing inflammation and reddening of eye can be treated with the addition of antioxidants in eye creams. Antioxidants are found naturally in the body and in plants such as fruits and vegetables. Common antioxidants include vitamin A, vitamin C, vitamin E, and certain compounds called carotenoids (e.g., lutein and beta-carotene). Antioxidants help to prevent the destruction of cells by bonding with free radicals. Free radicals are atoms or groups of atoms with an odd (unpaired) number of electrons and can be formed when oxygen interacts with certain molecules. Free radicals are often generated due to pollution and stress.
All the above literature cited information suggests the importance of tyrosinase enzyme inhibitors, hyaluronidase enzyme inhibitors and antioxidants as active ingredients in the formulation of under eye care cosmeceutical preparations for prevention and treatment of dark circles, puffiness of eyes, eye bags and fine wrinkles around the eyes etc. for human beings.
U.S. Pat. No. 6,682,763 to Kuno et al. describes the preparation of Skin-beautifying agent, anti-aging agent for the skin, whitening agent and external agent for the skin using multi herbal composition comprising Saxifraga stronifera Meerburg, marshmallow, Angelica keiskei Koidz, Artemisia capillaries herba, nettle, philodendron bark, Hypericum erectum, lonicerae flos, Salvia officinalis, lithospermum roots, white birch, Sapindus mukurossi Gaertn, etc.
U.S. Pat. No. 6,641,845 to Kyrou et al. demonstrates the preparation of skin whitening composition comprising bearberry and tetrahydrocurcumin.
U.S. Pat. No. 6,406,682 to Martin et al. teaches the use of Saxifraga extracts for artificial tanning of human skin.
U.S. Patent Application No. 20040115286 to Lee Kang Tae et al. discloses the preparation of herbal composition comprising the extract of Bergenia emeiensis for remedying skin wrinkles.
U.S. Patent Application No. 20050089589 to Chaudhuri et al. describes the use of Emblica officinalis extract as skin lightening agent.
U.S. Pat. No. 6,699,463 to Chaudhuri et al. discloses the preparation photostable sunscreen composition comprising Emblica officinalis extract as one of the antioxidant agent.
U.S. Pat. No. 6,235,721 to Ghosal et al. demonstrates a process for the stabilization of Vitamin C content as antioxidant from Emblica officinalis. 